Would it be possible to give the user a quick questionaire as to what subject they are doing at the start of the year or when they register? This information could be used to streamline the questions that come up on the homepage so, for example, if you are in second year and you are only doing Fin. Maths then on your home page (and Q&A page) only Fin. Maths questions come up. If you wanted to see what other questions there are you go to the catagory of your choosing. This will make it more convinient for the user to get straight to their relevant subject's questions. Otherwise this online hotseat is a fantastic idea!

I see your point (you don't want to see questions about things that mean nothing to you!). The main obstacle to your suggestion is that I don't really know how to implement it ;)

And besides, there is a big advantage of having a single feed: hopefully students in other years will see a question from a course they've done before and contribute an answer occasionally. The idea is that the site is community-driven and, where possible, students should always look to give something back :)